We have an old (but very important) production database that has recently started failing. The job history for the backup shows that the problem was with the Master database on that server, which gets backed up at the same time and took 2 days to backup. The Master database is currently 740Mb. We have truncated and dropped a table from the Master database that we know should have been in one of the non system databases. We now think we should shrink the master database. Is there any reason not to do this?